DataStream.assignTimestampsAndWatermarks will add a watermark generator operator after each source operator(if their parallelism is the same which is true for the code you showed) and so if one instance of the source operator has no data, the corresponding watermark generator operator cannot generate watermark.
Regards, Dian > 在 2019年2月20日，上午12:56，Stephen Connolly <stephen.alan.conno...@gmail.com> 写道： > > Though I am explicitly assigning watermarks with > DataStream.assignTimestampsAndWatermarks and I see all the data flowing > through that... so shouldn't that override the watermarks from the original > source? > > On Tue, 19 Feb 2019 at 15:59, Martin, Nick <nick.mar...@ngc.com > <mailto:nick.mar...@ngc.com>> wrote: > Yeah, that’s expected/known. Watermarks for the empty partition don’t > advance, so the window in your window function never closes. > > > > There’s a ticket open to fix it > (https://issues.apache.org/jira/browse/FLINK-5479 > <https://issues.apache.org/jira/browse/FLINK-5479>) for the kafka connector, > but in general any time one parallel instance of a source function isn’t > getting data you have to watch out for this. > > > > From: Stephen Connolly [mailto:stephen.alan.conno...@gmail.com > <mailto:stephen.alan.conno...@gmail.com>] > Sent: Tuesday, February 19, 2019 6:32 AM > To: user <user@flink.apache.org <mailto:user@flink.apache.org>> > Subject: EXT :Re: How to debug difference between Kinesis and Kafka > > > > Hmmm my suspicions are now quite high. I created a file source that just > replays the events straight then I get more results.... > > > > On Tue, 19 Feb 2019 at 11:50, Stephen Connolly > <stephen.alan.conno...@gmail.com <mailto:stephen.alan.conno...@gmail.com>> > wrote: > > Hmmm after expanding the dataset such that there was additional data that > ended up on shard-0 (everything in my original dataset was coincidentally > landing on shard-1) I am now getting output... should I expect this kind of > behaviour if no data arrives at shard-0 ever? > > > > On Tue, 19 Feb 2019 at 11:14, Stephen Connolly > <stephen.alan.conno...@gmail.com <mailto:stephen.alan.conno...@gmail.com>> > wrote: > > Hi, I’m having a strange situation and I would like to know where I should > start trying to debug. > > > > I have set up a configurable swap in source, with three implementations: > > > > 1. A mock implementation > > 2. A Kafka consumer implementation > > 3. A Kinesis consumer implementation > > > > From injecting a log and no-op map function I can see that all three sources > pass through the events correctly. > > > > I then have a window based on event time stamps… and from inspecting the > aggregation function I can see that the data is getting aggregated…, I’m > using the `.aggregate(AggregateFunction.WindowFunction)` variant so that I > can retrieve the key > > > > Here’s the strange thing, I only change the source (and each source uses the > same deserialization function) but: > > > > When I use either Kafka or my Mock source, the WindowFunction gets called as > events pass the end of the window > When I use the Kinesis source, however, the window function never gets > called. I have even tried injecting events into kinesis with really high > timestamps to flush the watermarks in my > BoundedOutOfOrdernessTimestampExtractor... but nothing > I cannot see how this source switching could result in such a different > behaviour: > > > > Properties sourceProperties = new Properties(); > > ConsumerFactory sourceFactory; > > String sourceName = configParams.getRequired("source"); > > switch (sourceName.toLowerCase(Locale.ENGLISH)) { > > case "kinesis": > > sourceFactory = FlinkKinesisConsumer::new; > > copyOptionalArg(configParams, "aws-region", sourceProperties, > AWSConfigConstants.AWS_REGION); > > copyOptionalArg(configParams, "aws-endpoint", > sourceProperties, AWSConfigConstants.AWS_ENDPOINT); > > copyOptionalArg(configParams, "aws-access-key", > sourceProperties, AWSConfigConstants.AWS_ACCESS_KEY_ID); > > copyOptionalArg(configParams, "aws-secret-key", > sourceProperties, AWSConfigConstants.AWS_SECRET_ACCESS_KEY); > > copyOptionalArg(configParams, "aws-profile", > sourceProperties, AWSConfigConstants.AWS_PROFILE_NAME); > > break; > > case "kafka": > > sourceFactory = FlinkKafkaConsumer010::new; > > copyRequiredArg(configParams, "bootstrap-server", > sourceProperties, "bootstrap.servers"); > > copyOptionalArg(configParams, "group-id", sourceProperties, > "group.id <http://group.id/>"); > > break; > > case "mock": > > sourceFactory = MockSourceFunction::new; > > break; > > default: > > throw new RuntimeException("Unknown source '" + sourceName + > '\''); > > } > > > > // set up the streaming execution environment > > final StreamExecutionEnvironment env = > StreamExecutionEnvironment.getExecutionEnvironment(); > > > > // poll watermark every second because using > BoundedOutOfOrdernessTimestampExtractor > > env.getConfig().setAutoWatermarkInterval(1000L); > > env.enableCheckpointing(5000); > > > > SplitStream<JsonNode> eventsByType = > env.addSource(sourceFactory.create( > > configParams.getRequired("topic"), > > new ObjectNodeDeserializationSchema(), > > sourceProperties > > )) > > .returns(ObjectNode.class) // the use of ConsumerFactory > erases the type info so add it back > > .name("raw-events") > > .assignTimestampsAndWatermarks( > > new > ObjectNodeBoundedOutOfOrdernessTimestampExtractor("timestamp", > Time.seconds(5)) > > ) > > .split(new JsonNodeOutputSelector("eventType")); > > ... > > eventsByType.select(...) > > .keyBy(new JsonNodeStringKeySelector("_key")) > > > .window(TumblingEventOffsetPerKeyEventTimeWindows.of(Time.seconds(windowDuration), > > (KeySelector<JsonNode, Time>) > TasksMain::offsetPerMaster)) > > .trigger(EventTimeTrigger.create()) > > .aggregate(new CountsAggregator<>(), new KeyTagger<>()) // > <==== The CountsAggregator is seeing the data > > .print() // <==== HERE is where we get no output from > Kinesis... but Kafka and my Mock are just fine! > > > > > > > > Notice: This e-mail is intended solely for use of the individual or entity to > which it is addressed and may contain information that is proprietary, > privileged and/or exempt from disclosure under applicable law. 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